Magento installs fine, and I can see frontend and backend with no issues. However I noticed there are no theme folders (blank and luma) where they were supposed to be. Blank and luma folders are only found at pub/static/frontend/Magento folder but not in app/design/frontend/Magento.
That is expected in the composer based Magento2 application or if you got the zip. All languages, modules, themes will be under <root>/vendor/magento. So, Blank theme can be found at <root>/vendor/magento/theme-frontend-blank